FB2026_01 , released March 12, 2026
FB2026_01 , released March 12, 2026
Gene: Dmel\Sgs4
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General Information
Symbol
Dmel\Sgs4
Species
D. melanogaster
Name
Salivary gland secretion 4
Annotation Symbol
CG12181
Feature Type
FlyBase ID
FBgn0003374
Gene Model Status
Stock Availability
Gene Summary
Contribute a Gene Snapshot for this gene.
Also Known As

Sgs-4, salivary gland secretion protein 4, Sgs

Key Links
Genomic Location
Cytogenetic map
Sequence location
Recombination map
1-2
RefSeq locus
NC_004354 REGION:3250089..3251040
Sequence
Genomic Maps
Other Genome Views
The following external sites may use different assemblies or annotations than FlyBase.
Function
Gene Ontology (GO) Annotations (3 terms)
Molecular Function (1 term)
Terms Based on Experimental Evidence (0 terms)
Terms Based on Predictions or Assertions (1 term)
CV Term
Evidence
References
inferred from experiment
Biological Process (1 term)
Terms Based on Experimental Evidence (1 term)
CV Term
Evidence
References
involved_in puparial adhesion
inferred from expression pattern
Terms Based on Predictions or Assertions (0 terms)
Cellular Component (1 term)
Terms Based on Experimental Evidence (1 term)
CV Term
Evidence
References
inferred from direct assay
Terms Based on Predictions or Assertions (0 terms)
Gene Group (FlyBase)
Protein Family (UniProt)
-
Protein Signatures (InterPro)
    -
    Summaries
    Gene Group (FlyBase)
    GLUE PROTEINS -
    Salivary gland secretion genes encode proteins that make up the glue produced by Drosophila larvae that serves to attach the pupa to an external substrate during metamorphosis. (Adapted from FBrf0241323.)
    Phenotypic Description (Red Book; Lindsley and Zimm 1992)
    Sgs4
    Encodes the salivary-gland glue protein, SGS4; this protein not required for viability, since non producers eclose normally; it varies in size owing to a variable number of copies of a heptapeptide repeat in an N-terminal tandem array. Expression of the virtually inactive allele, Sgs4H increased four fold in trans heterozygotes with the normally active allele, Sgs4OR, and nine fold with a tandem duplication [Dp(1;1)Co] containing two copies of a normally active allele; neither Sgs4H/Sgs4Ber nor Sgs4Ber/Sgs4OR exhibits enhanced activity; enhancement decreased by disruption in pairing, e.g., in Sgs4H/FM6 (Kornher and Brutlag, 1986, Cell 44: 879-83).
    Gene Model and Products
    Number of Transcripts
    1
    Number of Unique Polypeptides
    1

    Please see the JBrowse view of Dmel\Sgs4 for information on other features

    To submit a correction to a gene model please use the Contact FlyBase form

    Protein Domains (via Pfam)
    Isoform displayed:
    Pfam protein domains
    InterPro name
    classification
    start
    end
    Protein Domains (via SMART)
    Isoform displayed:
    SMART protein domains
    InterPro name
    classification
    start
    end
    Structure
    Protein 3D structure   (Predicted by AlphaFold)   (AlphaFold entry Q00725)

    If you don't see a structure in the viewer, refresh your browser.
    Model Confidence:
    • Very high (pLDDT > 90)
    • Confident (90 > pLDDT > 70)
    • Low (70 > pLDDT > 50)
    • Very low (pLDDT < 50)

    AlphaFold produces a per-residue confidence score (pLDDT) between 0 and 100. Some regions with low pLDDT may be unstructured in isolation.

    Experimentally Determined Structures
    Crossreferences
    Comments on Gene Model

    Low-frequency RNA-Seq exon junction(s) not annotated.

    Supported by strand-specific RNA-Seq data.

    Gene model reviewed during 5.46

    Gene model reviewed during 6.02

    Transcript Data
    Annotated Transcripts
    Name
    FlyBase ID
    RefSeq ID
    Length (nt)
    Assoc. CDS (aa)
    FBtr0346736
    952
    287
    Additional Transcript Data and Comments
    Reported size (kB)

    1.189 (sequence analysis)

    Comments
    External Data
    Crossreferences
    Polypeptide Data
    Annotated Polypeptides
    Name
    FlyBase ID
    Predicted MW (kDa)
    Length (aa)
    Theoretical pI
    UniProt
    RefSeq ID
    GenBank
    FBpp0312344
    31.0
    287
    9.07
    Polypeptides with Identical Sequences

    There is only one protein coding transcript and one polypeptide associated with this gene

    Additional Polypeptide Data and Comments
    Reported size (kDa)
    Comments

    Naturally occurring variant of Sgs4-P1.

    3'' sequence

    5'' sequence

    3' sequence

    Naturally occurring variant of Sgs4-P1; isolated from Samarkand strain.

    Glycosylation deduced from aberrant migration in acrylamide gels and PAS-staining.

    External Data
    Crossreferences
    Linkouts
    Sequences Consistent with the Gene Model
    Mapped Features

    Click to get a list of regulatory features (enhancers, TFBS, etc.) and gene disruptions (point mutations, indels, etc.) within or overlapping Dmel\Sgs4 using the Feature Mapper tool.

    External Data
    Crossreferences
    Eukaryotic Promoter Database - A collection of databases of experimentally validated promoters for selected model organisms.
    Linkouts
    Expression Data
    Testis-specificity index

    The testis specificity index was calculated from modENCODE tissue expression data by Vedelek et al., 2018 to indicate the degree of testis enrichment compared to other tissues. Scores range from -2.52 (underrepresented) to 5.2 (very high testis bias).

    -0.20

    Transcript Expression
    northern blot
    Stage
    Tissue/Position (including subcellular localization)
    Reference
    Additional Descriptive Data
    Marker for
     
    Subcellular Localization
    CV Term
    Polypeptide Expression
    dissected tissue
    Stage
    Tissue/Position (including subcellular localization)
    Reference
    Additional Descriptive Data

    Relative to one another, expression of Sgs6+P is observed first, Sgs3-XP, Sgs4+P, Sgs5-XP next (106-120 hours after hatching) and Sgs1-XP last.

    Marker for
     
    Subcellular Localization
    CV Term
    Evidence
    References
    inferred from direct assay
    Expression Deduced from Reporters
    High-Throughput Expression Data
    Associated Tools

    JBrowse - Visual display of RNA-Seq signals

    View Dmel\Sgs4 in JBrowse
    RNA-Seq by Region - Search RNA-Seq expression levels by exon or genomic region
    Reference
    See Gelbart and Emmert, 2013 for analysis details and data files for all genes.
    Developmental Proteome: Life Cycle
    Developmental Proteome: Embryogenesis
    External Data and Images
    Linkouts
    BDGP expression data - Patterns of gene expression in Drosophila embryogenesis
    DRscDB - A single-cell RNA-seq resource for data mining and data comparison across species
    EMBL-EBI Single Cell Expression Atlas - Single cell expression across species
    FlyAtlas - Adult expression by tissue, using Affymetrix Dros2 array
    FlyAtlas2 - A Drosophila melanogaster expression atlas with RNA-Seq, miRNA-Seq and sex-specific data
    Fly-FISH - A database of Drosophila embryo and larvae mRNA localization patterns
    Flygut - An atlas of the Drosophila adult midgut
    Images
    Alleles, Insertions, Transgenic Constructs, and Aberrations
    Classical and Insertion Alleles ( 20 )
    For All Classical and Insertion Alleles Show
     
    Other relevant insertions
    Transgenic Constructs ( 21 )
    For All Alleles Carried on Transgenic Constructs Show
    Transgenic constructs containing/affecting coding region of Sgs4
    Transgenic constructs containing regulatory region of Sgs4
    Aberrations (Deficiencies and Duplications) ( 7 )
    Variants
    Variant Molecular Consequences
    Alleles Representing Disease-Implicated Variants
    Phenotypes
    For more details about a specific phenotype click on the relevant allele symbol.
    Other Phenotypes
    Allele
    Phenotype manifest in
    Allele
    Orthologs
    Human Orthologs (via DIOPT v9.1)
    Species\Gene Symbol
    Score
    Best Score
    Best Reverse Score
    Alignment
    Complementation?
    Transgene?
    Homo sapiens (Human) (6)
    1 of 14
    Yes
    Yes
    1 of 14
    Yes
    Yes
    1 of 14
    Yes
    No
    1 of 14
    Yes
    No
    1 of 14
    Yes
    No
    1 of 14
    Yes
    No
    Model Organism Orthologs (via DIOPT v9.1)
    Species\Gene Symbol
    Score
    Best Score
    Best Reverse Score
    Alignment
    Complementation?
    Transgene?
    Rattus norvegicus (Norway rat) (6)
    2 of 14
    Yes
    Yes
    1 of 14
    No
    Yes
    1 of 14
    No
    Yes
    1 of 14
    No
    Yes
    1 of 14
    No
    No
    1 of 14
    No
    No
    Mus musculus (laboratory mouse) (4)
    1 of 14
    Yes
    Yes
    1 of 14
    Yes
    Yes
    1 of 14
    Yes
    No
    1 of 14
    Yes
    No
    Xenopus tropicalis (Western clawed frog) (1)
    1 of 13
    Yes
    No
    Danio rerio (Zebrafish) (8)
    2 of 14
    Yes
    Yes
    1 of 14
    No
    Yes
    1 of 14
    No
    Yes
    1 of 14
    No
    Yes
    1 of 14
    No
    No
    1 of 14
    No
    No
    Caenorhabditis elegans (Nematode, roundworm) (24)
    1 of 14
    Yes
    Yes
    1 of 14
    Yes
    Yes
    1 of 14
    Yes
    Yes
    1 of 14
    Yes
    Yes
    1 of 14
    Yes
    Yes
    1 of 14
    Yes
    Yes
    1 of 14
    Yes
    Yes
    1 of 14
    Yes
    Yes
    1 of 14
    Yes
    Yes
    1 of 14
    Yes
    Yes
    1 of 14
    Yes
    No
    1 of 14
    Yes
    No
    1 of 14
    Yes
    Yes
    1 of 14
    Yes
    Yes
    1 of 14
    Yes
    Yes
    1 of 14
    Yes
    Yes
    1 of 14
    Yes
    Yes
    1 of 14
    Yes
    Yes
    1 of 14
    Yes
    Yes
    1 of 14
    Yes
    Yes
    1 of 14
    Yes
    Yes
    1 of 14
    Yes
    Yes
    1 of 14
    Yes
    No
    1 of 14
    Yes
    Yes
    Anopheles gambiae (African malaria mosquito) (3)
    1 of 12
    Yes
    Yes
    Arabidopsis thaliana (thale-cress) (4)
    1 of 13
    Yes
    No
    1 of 13
    Yes
    Yes
    1 of 13
    Yes
    Yes
    1 of 13
    Yes
    Yes
    Saccharomyces cerevisiae (Brewer's yeast) (0)
    Schizosaccharomyces pombe (Fission yeast) (0)
    Escherichia coli (enterobacterium) (0)
    Other Organism Orthologs (via OrthoDB)
    Data provided directly from OrthoDB:Sgs4. Refer to their site for version information.
    Paralogs
    Paralogs (via DIOPT v9.1)
    Drosophila melanogaster (Fruit fly) (3)
    1 of 13
    1 of 13
    1 of 13
    Human Disease Associations
    FlyBase Human Disease Model Reports
      Disease Ontology (DO) Annotations
      Models Based on Experimental Evidence ( 0 )
      Allele
      Disease
      Evidence
      References
      Potential Models Based on Orthology ( 0 )
      Human Ortholog
      Disease
      Evidence
      References
      Modifiers Based on Experimental Evidence ( 0 )
      Allele
      Disease
      Interaction
      References
      Disease Associations of Human Orthologs (via DIOPT v9.1 and OMIM)
      Note that ortholog calls supported by only 1 or 2 algorithms (DIOPT score < 3) are not shown.
      Homo sapiens (Human)
      Gene name
      Score
      OMIM
      OMIM Phenotype
      DO term
      Complementation?
      Transgene?
      Functional Complementation Data
      Functional complementation data is computed by FlyBase using a combination of the orthology data obtained from DIOPT and OrthoDB and the allele-level genetic interaction data curated from the literature.
      Interactions
      Summary of Physical Interactions
      Interaction Browsers
      Summary of Genetic Interactions
      Interaction Browsers
      Starting gene(s)
      Interaction type
      Interacting gene(s)
      Reference
      Starting gene(s)
      Interaction type
      Interacting gene(s)
      Reference
      External Data
      Linkouts
      DroID - A comprehensive database of gene and protein interactions.
      Pathways
      Signaling Pathways (FlyBase)
      Metabolic Pathways
      FlyBase
      External Links
      External Data
      Linkouts
      Class of Gene
      Genomic Location and Detailed Mapping Data
      Chromosome (arm)
      X
      Recombination map
      1-2
      Cytogenetic map
      Sequence location
      FlyBase Computed Cytological Location
      Cytogenetic map
      Evidence for location
      3C10-3C10
      Limits computationally determined from genome sequence between P{EP}dncEP1395 and P{EP}dncEP973
      Experimentally Determined Cytological Location
      Cytogenetic map
      Notes
      References
      3C11-3C12
      (determined by in situ hybridisation)
      3C11-3C11
      (determined by in situ hybridisation)
      The Sgs4 gene colocalizes with the 3C intermolt puff.
      Associated with the intermolt puff in 3C-11.
      Experimentally Determined Recombination Data
      Left of (cM)
      Right of (cM)
      Notes

      Mapping based on 97 wa-rb recombinants.

      Stocks and Reagents
      Stocks (4)
      Genomic Clones (12)
       

      Please Note FlyBase no longer curates genomic clone accessions so this list may not be complete

      cDNA Clones (1)
       

      Please Note This section lists cDNAs and ESTs that fall within the genomic extent of the gene model, which may include cDNAs and ESTs of genes within introns, or of overlapping genes. Please see JBrowse for alignment of the cDNAs and ESTs to the gene model.

      cDNA clones, fully sequenced
      BDGP DGC clones
        Other clones
          Drosophila Genomics Resource Center cDNA clones

          For each fully sequenced cDNA the DGRC maintains various forms of the cDNA (e.g tagged or untagged) in several different host vectors for subsequent cloning and expression in Drosophila and Drosophila cell lines.

          cDNA Clones, End Sequenced (ESTs)
          BDGP DGC clones
            Other clones
              RNAi and Array Information
              Linkouts
              DRSC - Results frm RNAi screens
              Antibody Information
              Laboratory Generated Antibodies
               
              Commercially Available Antibodies
               
              Cell Line Information
              Publicly Available Cell Lines
               
                Other Stable Cell Lines
                 
                  Other Comments

                  Downregulation of fkh at puparium formation is necessary for proper repression of Sgs4.

                  The transcriptional switch between Pig1 and Sgs4 depends on a SEBP1 binding site within a shared enhancer region.

                  fkh protein binds to multiple sites in the Sgs4 upstream region. The fkh binding sites of the EcRU (ecdysone response unit) are necessary for full transcriptional induction of Sgs4.

                  Sgs4 RNA expression has been analysed in wild-type and br mutant larvae.

                  Gene expression is unaffected in Eip74EFneo24 mutants but transcripts are moderately affected in Eip74EFDL-1 mutants.

                  The EcR product binds to two sites, element I and element II, in the regulatory region of Sgs4. Element II appears to be of no importance for the expression of Sgs4 while element I is an ecdysone response element necessary, but not sufficient, for Sgs4 induction. Close to elements I and II lie two binding sites for the Sebp3 product. One of these sites is necessary but not sufficient for Sgs4 expression. This hormone response unit also contains binding sites for the fkh product, which coincide with binding sites for Broad Complex products.

                  Cis-acting sequences required for dosage compensation are located within 840bp upstream of the gene. Germline transformation studies and a comparison of sequences from several dosage compensation genes reveal sequences within the coding region and/or downstream of the gene also play a role in dosage compensation.

                  There is evidence that the br-C directly mediates the ecdysone-dependent transcriptional switch, that leads to Sgs4 induction and Pig1 repression, by binding to sites within element III.

                  Ecdysteroid-regulated gene.

                  An investigation of the relationship between transcription, puffing and hormone regulation of intermoult puff was analysed using ecd1 mutant embryos: Sgs4 expression is severely reduced by shifting ecd1 embryos to the restrictive temperature, 30oC. Normal sized 3C11-12 puff can be formed in conditions in which Sgs4 transcription is severely reduced.

                  Sgs4 encodes a salivary-gland glue protein. One of a group of seven genes encoding proteins that are components of the secretion produced by the larval salivary glands during the third instar for the purpose of attaching the larva to the substrate preparative to pupariation.

                  Sgs3, Sgs4 and Sgs5 transcript levels were very low in hemizygous brrbp-1 larvae and pupae.

                  Adh reporter gene constructs demonstrate Sgs4 is expressed throughout development in the proventriculus and salivary glands. This expression pattern differs form other glue genes and is unique to Sgs4.

                  The region of Sgs4 needed for developmentally regulated puffing is defined as a 2.5kb 5' upstream fragment. Puff formation requires only the 840bp promoter region, formation of cytologically visible puff depends on the strength of the promoter. Puff formation therefore depends on a cis-acting element which functions through interaction with trans-acting factors.

                  Sgs4 transcription in cultured wild-type and su(f)8 third instar larval salivary glands in the presence and absence of 20-OH-ecdysone has been studied.

                  Three elements necessary for tissue specificity within an Sgs4 enhancer have been identified using Sgs4-Adh regulatory fusion constructs.

                  Pig1 and Sgs4 are located within the 79kb intron of the dnc gene. Pig1 is transcribed from the opposite strand to dnc and Sgs4.

                  The ability of a cis-acting upstream regulatory region of Sgs4 to act as an enhancer has been studied in Adh-Sgs4 regulatory fusion genes.

                  Germline transformation studies demonstrate that most sequences required for normal Sgs4 expression lie in a 1.9kb region.

                  Cessation of Sgs4 transcription and puff regression are ecdysterone-dependent.

                  Initiation of transcription of Sgs4, but not of intermolt-puff formation seems to depend on the presence of suitable levels of ecdysterone in early third instar larvae.

                  A complex of five tissue-specific DNAase-hypersensitive sites is present 5' to Sgs4 in chromatin from third instar salivary glands.

                  Synthesis of the glue proteins begins about 106 h after egg deposition and ceases abruptly within a few minutes after the glue is released 14 h later.

                  Initiation of transcription of Sgs4 is coincident with the formation of the intermolt puffs in early to mid third instar.

                  Relationship to Other Genes
                  Source for database merge of
                  Additional comments

                  The Sgs4 gene may have been derived from the CG34324 gene, but as the region of similarity between the two genes does not span an exon-exon junction in the parental gene, retroposition cannot necessarily be inferred.

                  Nomenclature History
                  Source for database identify of
                  Nomenclature comments
                  Etymology
                  Synonyms and Secondary IDs (11)
                  Reported As
                  Symbol Synonym
                  EG:96G10.6
                  Name Synonyms
                  Salivary gland secretion 4
                  salivary gland secretion protein 4
                  Secondary FlyBase IDs
                    Datasets (0)
                    Study focus (0)
                    Experimental Role
                    Project
                    Project Type
                    Title
                    Study result (0)
                    Result
                    Result Type
                    Title
                    External Crossreferences and Linkouts ( 69 )
                    Sequence Crossreferences
                    NCBI Gene - Gene integrates information from a wide range of species. A record may include nomenclature, Reference Sequences (RefSeqs), maps, pathways, variations, phenotypes, and links to genome-, phenotype-, and locus-specific resources worldwide.
                    GenBank Protein - A collection of sequences from several sources, including translations from annotated coding regions in GenBank, RefSeq and TPA, as well as records from SwissProt, PIR, PRF, and PDB.
                    RefSeq - A comprehensive, integrated, non-redundant, well-annotated set of reference sequences including genomic, transcript, and protein.
                    UniProt/GCRP - The gene-centric reference proteome (GCRP) provides a 1:1 mapping between genes and UniProt accessions in which a single 'canonical' isoform represents the product(s) of each protein-coding gene.
                    UniProt/Swiss-Prot - Manually annotated and reviewed records of protein sequence and functional information
                    Other crossreferences
                    AlphaFold DB - AlphaFold provides open access to protein structure predictions for the human proteome and other key proteins of interest, to accelerate scientific research.
                    BDGP expression data - Patterns of gene expression in Drosophila embryogenesis
                    DRscDB - A single-cell RNA-seq resource for data mining and data comparison across species
                    EMBL-EBI Single Cell Expression Atlas - Single cell expression across species
                    FlyAtlas2 - A Drosophila melanogaster expression atlas with RNA-Seq, miRNA-Seq and sex-specific data
                    FlyMine - An integrated database for Drosophila genomics
                    KEGG Genes - Molecular building blocks of life in the genomic space.
                    MARRVEL_MODEL - MARRVEL (model organism gene)
                    Linkouts
                    Drosophila Genomics Resource Center - Drosophila Genomics Resource Center (DGRC) cDNA clones
                    DroID - A comprehensive database of gene and protein interactions.
                    DRSC - Results frm RNAi screens
                    Eukaryotic Promoter Database - A collection of databases of experimentally validated promoters for selected model organisms.
                    FlyAtlas - Adult expression by tissue, using Affymetrix Dros2 array
                    FlyCyc Genes - Genes from a BioCyc PGDB for Dmel
                    Fly-FISH - A database of Drosophila embryo and larvae mRNA localization patterns
                    Flygut - An atlas of the Drosophila adult midgut
                    iBeetle-Base - RNAi phenotypes in the red flour beetle (Tribolium castaneum)
                    References (173)